Laminator

ABSTRACT

The present invention provides a laminator capable of improving evenness of a pressing force applied from pressure-bonding rolls to a substrate and a film. 
     The laminator includes a first pressure-bonding roll, and a second pressure-bonding roll disposed above the first pressure-bonding roll and configured to be displaceable in a direction toward (a first direction) and a direction away from (a second direction) the first pressure-bonding roll. The laminator further includes a support roll configured to support the first pressure-bonding roll below the first pressure-bonding roll, and a pressure application roll disposed above the second pressure-bonding roll. The pressure application roll is configured to be displaceable in the first direction and the second direction, and is also configured to press the second pressure-bonding roll toward one side where the first pressure-bonding roll is located by being displaced in the first direction. The laminator further includes a driving mechanism configured to displace the pressure application roll in the first direction and the second direction.

TECHNICAL FIELD

The present invention relates to a technique for pressure-bonding a film onto a substrate.

BACKGROUND ART

There are known a laminator that pressure-bonds a film containing a photosensitive material (a photoresist) onto one side or each of both sides of a substrate with use of a pair of pressure-bonding rolls. The laminator supplies the substrate into between the pair of pressure-bonding rolls and also supplies the film onto at least one surface of the substrate, sandwiches the substrate and the film between the pair of pressure-bonding rolls, and heats the substrate while causing the pair of pressure-bonding rolls to apply a predetermined pressing force toward a substrate side, thereby pressure-bonding the film onto the substrate. The substrate with the film pressure-bonded thereon in this manner is exposed to light, by which a conductive pattern or the like is formed on this substrate.

Generally, a pressing force to the pressure-bonding rolls is applied to bearing housings that support bearings provided at both ends of the pressure-bonding rolls, with use of an actuator, such as an air cylinder. This commonly used laminator leads to application of the pressing force to the both ends of the pair of pressure-bonding rolls toward the substrate side. Therefore, when a relatively thick substrate is processed, a bending moment (hereinafter referred to as a first bending moment) is generated on the pair of pressure-bonding rolls with edges of both ends of the substrate serving as supports As a result, the pressure-bonding rolls are each deformed into such an arch shape that a center thereof is distanced farther away from the substrate than the both ends thereof. This deformation results in uneven application of the pressing force from the pressure-bonding rolls to the substrate and the film in a direction in which the pressure-bonding rolls extend.

Under such environments, there is developed a technique that allows the pressure-bonding rolls to apply the pressing force so as to generate a second bending moment in an opposite direction from the first bending moment at the same time as generating the first bending moment (for example, the following patent literatures, PTLs 1 and 2). According to this technique, the first bending moment and the second bending moment cancel out each other's influence causing the bending of the pressure-bonding rolls, which can reduce the deformation of the pressure-bonding rolls to thereby improve the unevenness of the pressing force. Further, another possible method is to form each of the pressure-bonding rolls in such a manner that an outer diameter thereof is increasing from the both ends toward the center, thereby establishing even contact between a shape of the arched deformed pressure-bonding roll and shapes of the substrate and the film to improve the unevenness of the pressing force. The roll shaped in this manner is called a crown roll.

CITATION LIST Patent Literature

PTL 1: Japanese Patent No. 3725638

PTL 2: Japanese Patent No. 4141142

SUMMARY OF INVENTION Technical Problem

However, the method that generates the second bending moment cannot completely resolve the deformation of the pressure-bonding rolls, and therefore is desired to further improve the evenness of the pressing force. On the other hand, the method using the crown roll requires a high processing accuracy and therefore makes the manufacturing difficult. As a result, in reality, it is difficult to attain the effect of achieving the evenness of the pressing force by this method. Further, the laminator is subject to deposition of dirt and foreign objects (for example, a photoresist) on the pressure-bonding rolls, whereby the pressure-boning rolls should be replaced on a regular basis. This replacement process is desired to be easy, safe, and quick to complete. However, the conventional pressure-bonding rolls are relatively heavy in weight because of their configurations, and therefore should be processed with safety fully in mind and cannot be replaced until the pressure-bonding rolls cool down to a certain level of temperature. Further, another conceivable solution is to increase diameters of the pressure-bonding rolls to enhance rigidity thereof, thereby preventing or reducing the deformation of the pressure-bonding rolls. However, consideration of process efficiency and safety of the above-described replacement process imposes a limit on the increases in the diameters of the pressure-bonding rolls. Therefore, it is not practical to prevent or reduce the deformation of the pressure-bonding rolls by increasing the diameters of the pressure-bonding rolls.

Solution to Problem

The present invention has been made to solve at least a part of the above-described problem, and can be embodied as, for example, the following embodiments.

A first embodiment of the present invention is provided as a laminator for pressure-bonding a film onto a substrate. This laminator includes a pair of pressure-bonding rolls. The pair of pressure-bonding rolls includes a positionally fixed first pressure-bonding roll, and a second pressure-bonding roll disposed above the first pressure-bonding roll and configured to be displaceable in a direction toward the first pressure-bonding roll and a direction away from the first pressure-bonding roll. The pair of pressure-bonding rolls pressure-bonds the film onto the substrate by sandwiching the substrate and the film between the first pressure-bonding roll and the second pressure-bonding roll. The laminator further includes a support roll disposed in parallel with the first pressure-bonding roll below the first pressure-bonding roll and configured to support the first pressure-bonding roll, and a pressure application roll disposed in parallel with the second pressure-bonding roll above the second pressure-bonding roll. The pressure application roll is configured to be displaceable in a first direction that is the direction in which the second pressure-bonding roll is displaced toward the first pressure-bonding roll, and a second direction that is the direction in which the second pressure-bonding roll is displaced away from the first pressure-bonding roll, and is also configured to press the second pressure-bonding roll toward one side where the first pressure-bonding roll is located by being displaced in the first direction. The laminator further includes a driving mechanism configured to displace the pressure application roll in the first direction and the second direction.

According to the thus-configured laminator, the film can be pressure-bonded onto each of both surfaces or one surface of the substrate by displacing the pressure application roll in the first direction (the direction in which the second pressure-bonding roll is displaced toward the first pressure-bonding roll), thereby displacing the second pressure-bonding roll closer to the substrate to apply a pressing force to the substrate and the film between the first pressure-bonding roll and the second pressure-bonding roll. The pressure application roll and the support roll do not contact the film at this time, and therefore normally do not have to be replaced. Therefore, the support roll and the pressure application roll can be increased in diameter and thus enhanced in rigidity without requiring increases in diameters of the first pressure-bonding roll and the second pressure-bonding roll, which can prevent or reduce deformation of the first pressure-bonding roll and the second pressure-bonding roll and achieve evenness of the pressing force. In other words, the present laminator can realize both the improvement of process efficiency regarding the replacement of the component and the evenness of the pressing force at the same time. Furthermore, the pressure application roll presses the second pressure-bonding roll along a line, so that an even pressure distribution can be acquired compared to the laminator that presses the ends of the second pressure-bonding roll toward the substrate. Further, the first pressure-bonding roll and the second pressure-bonding roll do not have to be increased in diameter to achieve the evenness of the pressing force, i.e., the first pressure-bonding roll and the second pressure-bonding roll can be kept small in diameter, which leads to an increase in a linear pressure in a direction in which the first pressure-bonding roll and the second pressure-bonding roll extend when the film is pressure-bonded. As a result, the film can be pressure-bonded onto the substrate with a further low pressing force. Further, the present laminator allows the first pressure-bonding roll and the second pressure-bonding roll to be reduced in diameter, i.e., lightened in weight, thereby making easy and safe a process of attaching and detaching the first pressure-bonding roll and the second pressure-bonding roll. Furthermore, this configuration also leads to reductions in heat capacities of the first pressure-bonding roll and the second pressure-bonding roll due to the reductions in the respective diameters of the first pressure-bonding roll and the second pressure-bonding roll, thereby allowing respective temperatures of the first pressure-bonding roll and the second pressure-bonding roll to drop quickly after an operation of the laminator is stopped. Therefore, the process of detaching and attaching the first pressure-bonding roll and the second pressure-bonding roll can be started soon after the operation of the laminator is stopped.

As a second embodiment of the present invention, in the first embodiment, the support roll may be disposed in contact with the first pressure-bonding roll. The pressure application roll may contact the second pressure-bonding roll at least when the pressure application roll is displaced in the first direction. The pair of pressure-bonding rolls may pressure-bond the film onto the substrate by sandwiching the substrate and the film directly between the first pressure-bonding roll and the second pressure-bonding roll. According to this embodiment, advantageous effects of the first embodiment can be preferably achieved.

As a third embodiment of the present invention, in the first or second embodiment, the support roll may include a first heating unit inside the support roll. The pressure application roll may include a second heating unit inside the pressure application roll. According to this embodiment, the first pressure-bonding roll and the second pressure-bonding roll can be heated by indirect heating. This embodiment allows the first pressure-bonding roll and the second pressure-bonding roll to be further reduced in diameter, and also allows the first pressure-bonding roll and the second pressure-bonding roll to cool down quickly, compared to the first pressure-bonding roll and the second pressure-bonding roll including respective heating units therein. Therefore, this embodiment can further enhance the advantageous effect of the first embodiment due to the reductions in the diameters of the first pressure-bonding roll and the second pressure-bonding roll.

As a fourth embodiment of the present invention, the laminator according to the third embodiment may include a biasing member configure to keep the second pressure-bonding roll and the pressure application roll in contact with each other by biasing the second pressure-bonding roll toward one side where the pressure application is located. According to this embodiment, even when the pressure application roll is displaced in the second direction (the direction in which the second pressure-bonding roll is displaced away from the first pressure-bonding roll), the second pressure-bonding roll and the pressure application roll are kept in contact with each other, which allows heat of the heating unit included in the pressure application roll to be constantly transmitted to the second pressure-bonding roll. Therefore, the second pressure-bonding roll can be efficiently indirectly heated with the aid of the heating unit included in the pressure application roll. In addition, even when the pressure application roll is displaced in the second direction after the film is pressure-bonded onto a first substrate, a temperature of the second pressure-bonding roll does not drop. This means that, when the film is pressure-bonded onto a second substrate successively after the first substrate, the present laminator does not require a time to increase the temperature of the second pressure-bonding roll again. Therefore, the present laminator can efficiently perform the process of pressure-bonding the film, and provide high manufacturing efficiency. In other words, the laminator can perform the lamination processing on the substrate successively, thereby realizing productivity equivalent to a direct heating method, even though employing an indirect heating method like the second embodiment.

As a fifth embodiment of the present invention, the laminator according to any of the second to fourth embodiments may include a holding member configured to hold the first pressure-bonding roll and the second pressure-bonding roll, and configured detachably from the laminator together with the first pressure-bonding roll and the second pressure-bonding roll with the first pressure pressure-bonding roll and the second pressure-bonding roll remaining held by the holding member. According to this embodiment, when the first pressure-bonding roll and the second pressure-bonding roll fall in need of replacement due to, for example, deposition of a photoresist contained in the film on the first pressure-bonding roll and the second pressure-bonding roll by a predetermined amount, the first pressure-bonding roll and the second pressure-bonding roll can be easily replaced at the same time by detaching the holding member from the laminator, whereby the replacement process can be efficiently performed.

As a sixth embodiment of the present invention, the laminator according to the first embodiment may include a first tension roll and a second tension roll, a first annular flat belt extending across between the first pressure-bonding roll and the first tension roll, and a second annular flat belt extending across between the second pressure-bonding roll and the second tension roll. According to this embodiment, the film can be pressure-bonded onto each of the both surfaces or the one surface of the substrate by displacing the pressure application roll in the first direction (the direction in which the second pressure-bonding roll is displaced toward the first pressure-bonding roll) with use of the driving mechanism, thereby displacing the second annular flat belt and the second pressure-bonding roll closer to the substrate to apply the pressing force to the substrate and the film between the first annular flat belt and the second annular flat belt. Then, when a photoresist is deposited on the first annular flat belt or the second annular flat belt by a predetermined amount, the first annular flat belt or the second annular flat belt can be replaced by itself. In other words, the first pressure-bonding roll and the second pressure-bonding roll do not have to be replaced. The conventional method, which involves the contact of the pressure-bonding rolls to the film, requires preparation of spares of the pressure-bonding rolls in advance and replacement of the components including the pressure-bonding rolls to prevent the lamination processing from being interrupted for a long time. On the other hand, the process of replacing the annular flat belt is easy and does not require a long time. Therefore, when the annular flat belt falls in need of replacement, the annular flat belt can be replaced and the lamination processing can be resumed quickly. In other words, just preparing spares of the annular flat belts in advance can eliminate the necessity of interrupting the lamination processing for a long time. The annular flat belts are available at an extremely low price compared to the pressure-bonding rolls, whereby the present laminator can considerably save a cost regarding spare items that should be prepared.

As a seventh embodiment of the present invention, in the sixth embodiment, the support roll may include a first heating unit inside the support roll. The pressure application roll may include a second heating roll inside the pressure application roll. According to this embodiment, similar advantageous effects to the third embodiment can be achieved.

As an eighth embodiment of the present invention, the laminator according to the seventh embodiment may include a biasing member configured to keep the second annular flat belt and the pressure application roll in contact with each other by biasing the second pressure-bonding roll toward one side where the pressure application is located. According to this embodiment, heat of the heating unit included in the pressure application roll is constantly transmitted to the second annular flat belt. Therefore, similar advantageous effects to the fourth embodiment can be achieved.

As a ninth embodiment of the present invention, the laminator according to any of the sixth to eighth embodiments may include a holding member configured to hold the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll in such a positional relationship that respective tension forces of the first annular flat belt and the second annular flat belt are kept at tension forces required when the laminator is in operation. According to this embodiment, mounting the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll onto the holding member results in automatic adjustment of the tensions of the first annular flat belt and the second annular flat belt. Therefore, this embodiment facilitates the process of replacing the first annular flat belt and the second annular flat belt.

As a tenth embodiment of the present invention, in the ninth embodiment, the holding member may be configured detachably from the laminator together with the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll with the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll remaining held by the holding member. According to this embodiment, when the first annular flat belt or the second annular flat belt falls in need of replacement due to deposition of the photoresist on the first annular flat belt or the second annular flat belt by the predetermined amount, the first annular flat belt or the second annular flat belt can be easily replaced by detaching the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, the second tension roll, the first annular flat belt, the second annular flat belt, and the holding member from the laminator.

As an eleventh embodiment of the present invention, in any of the first to tenth embodiments, an outer diameter of the first pressure-bonding roll may be smaller than an outer diameter of the support roll. An outer diameter of the second pressure-bonding roll may be smaller than an outer diameter of the pressure application roll. According to this embodiment, the first pressure-bonding roll and the second pressure-bonding roll can be lightened in weight, as a result of which the first pressure-bonding roll and the second pressure-bonding roll can be easily attached and detached. Moreover, the reductions in the respective diameters of the first pressure-bonding roll and the second pressure-bonding roll lead to the enhancement of the linear pressure in the direction in which the first pressure-bonding roll and the second pressure-bonding roll extend when the film is pressure-bonded, whereby the film can be pressure-bonded onto the substrate with a further low pressing force.

The present invention can be realized in various embodiment, such as a set of the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, the second tension roll, the first annular flat belt, and the second annular flat belt, a set of this set and the holding member thereof, a set of the first pressure-bonding roll and the second pressure-bonding roll and the holding member thereof, and a method of pressure-bonding the film onto the substrate, besides the above-described laminator.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 schematically illustrates a configuration of a lamination unit (when not carrying out pressure-bonding) as one embodiment of the present invention.

FIG. 2 schematically illustrates the configuration of the lamination unit (when carrying out the pressure-bonding).

FIG. 3 illustrates how to detach and attach a first pressure-bonding roll and a second pressure-bonding roll.

FIG. 4 illustrates how to detach and attach the first pressure-bonding roll and the second pressure-bonding roll.

FIG. 5 illustrates how to detach and attach the first pressure-bonding roll and the second pressure-bonding roll.

FIG. 6 schematically illustrates a configuration of a lamination unit (when not carrying out the pressure-bonding) as a second embodiment.

DESCRIPTION OF EMBODIMENTS A. First Embodiment

A laminator as a first embodiment of the present invention will be described. This laminator includes a lamination unit 10, which pressure-bonds a film onto a substrate, a substrate conveyance apparatus, which conveys the substrate, and a film conveyance apparatus, which conveys the film. The substrate conveyance apparatus and the film conveyance apparatus can be embodied by employing known various apparatuses, whereby the following description will focus on only the lamination unit 10 with reference to the drawings illustrating only the lamination unit 10. FIG. 1 schematically illustrates a configuration of the lamination unit 10. FIG. 1(b) is a front view of the lamination unit 10, and illustrates the lamination unit 10 partially in cross section. FIG. 1(a) illustrates the lamination unit 10 illustrated in FIG. 1(b) taken along a line indicated by arrows A and A. Film guides 65 and 66 and films F illustrated in FIG. 1(a) (details thereof will be described below) are omitted from the illustration of FIG. 1(b). As illustrated in FIGS. 1(a) and 1(b), the lamination unit 10 includes a pair of pressure-bonding rolls, i.e., a first pressure-bonding roll 20 and a second pressure-bonding roll 30, a first tension roll 23 and a second tension roll 33, a first annular flat belt 24 and a second annular flat belt 34, a support roll 40, a pressure application roll 50, driving mechanisms 61 and 62, and a holding member 70.

The first pressure-bonding roll 20 is formed so as to extend in a horizontal direction (a direction perpendicular to a vertical direction), and is rotatably borne by a pair of bearings 21 and 22 provided at both ends of the first pressure-bonding roll 20. The second pressure-bonding roll 30 is formed so as to extend in the horizontal direction, and is disposed in parallel with the first pressure-bonding roll 20 above the first pressure-bonding roll 20. This second pressure-bonding roll 30 is rotatably borne by a pair of bearings 31 and 32 provided at both ends thereof. The first pressure-bonding roll 20 is positionally fixed, but the second pressure-bonding roll 30 is configured to be displaceable in a direction toward the first pressure-bonding roll 20 (also referred to as a first direction) and a direction away from the first pressure-bonding roll 20 (also referred to as a second direction). In the present embodiment, the first direction and the second direction are the vertical direction. The direction in which the second pressure-bonding roll 30 is displaced is not limited to the vertical direction, and the displacement of the second pressure-bonding roll 30 can be a displacement in any directions toward and away from the first pressure-bonding roll 20. FIG. 1 illustrates the lamination unit 10 after the second pressure-bonding roll 30 is displaced in the direction away from the first pressure-bonding roll 20. A configuration for displacing the second pressure-bonding roll 30 will be described below.

The first tension roll 23 is spaced apart from the first pressure-bonding roll 20 in the horizontal direction, and is disposed slightly below the first pressure-bonding roll 20 in the vertical direction. The first annular flat belt 24 extends across between the first tension roll 23 and the first pressure-bonding roll 20. The second tension roll 33 is spaced apart from the second pressure-bonding roll 30 in the horizontal direction, and is disposed slightly above the second pressure-bonding roll 30 in the vertical direction. The second annular flat belt 34 extends across between the second tension roll 33 and the second pressure-bonding roll 30.

The support roll 40 is formed so as to extend in the horizontal direction, and is disposed in parallel with the first pressure-bonding roll 20 below the first pressure-bonding roll 20. The support roll 40 is rotatably borne by a pair of bearings 41 and 42 provided at both ends thereof. The bearings 41 and 42 are positionally fixed, as a result of which the support roll 40 is also positionally fixed. This support roll 40 supports the first pressure-bonding roll 20 via the first annular flat belt 24. Inside the support roll 40, a heater 45 as a heating unit is provided along a direction in which the support roll 40 extends. The first annular flat belt 24 is disposed in contact with both the first pressure-bonding roll 20 and the support roll 40 between the first pressure-bonding roll 20 and the support roll 40. Therefore, a heat of the heater 45 is transmitted to the first annular flat belt 24 and the first pressure-bonding roll 20.

The pressure application roll 50 is formed so as to extend in the horizontal direction, and is disposed in parallel with the second pressure-bonding roll 30 above the second pressure-bonding roll 30. The pressure application roll 50 is rotatably borne by a pair of bearings 51 and 52 provided at both ends thereof. The bearings 51 and 52 are supported by bearing casings 53 and 54, respectively. Inside the pressure application roll 50, a heater 55 as a heating unit is provided along a direction in which the pressure application roll 50 extends. This pressure application roll 50 is configured to be displaceable in the above-described first direction (the direction in which the second pressure-bonding roll 30 is displaced toward the first pressure-bonding roll 20) and the above-described second direction (the direction in which the second pressure-bonding roll 30 is displaced away from the first pressure-bonding roll 20). More specifically, the driving mechanisms 61 and 62 are provided above the both end sides of the pressure application roll 50. The driving mechanisms 61 and 62 downwardly press the bearing casings 53 and 54, respectively. This pressing causes the bearing casings 53 and 54 to be displaced downwardly along guides 63 and 64 extending in the vertical direction together with the bearings 51 and 52, respectively, and thus the pressure application roll 50 borne by the bearings 51 and 52 to be translationally displaced downwardly according thereto. In this manner, the pressure application roll 50 is displaced in the first direction (in the present example, downwardly), which allows the second pressure-bonding roll 30 to be pressed and displaced toward one side where the first pressure-bonding roll 20 is located. FIG. 1 illustrates the lamination unit 10 before the pressure application roll 50 is displaced in the first direction. Each of the driving mechanisms 61 and 62 is an air cylinder in the present embodiment, but can be embodied by any actuator, such as a motor.

In the above-described lamination unit 10, the pressure-bonding rolls 20 and 30, the tension rolls 23 and 33, and the annular flat belts 24 and 34 are held by the holding member 70. The holding member 70 includes side plates 71 and 72, guides 73 and 74, springs 75 and 76 as biasing members, support plates 77 and 78, and four tie rods 79 a to 79 d. The side plates 71 and 72 are disposed so as to be located opposite from each other in the horizontal direction outside the pressure-bonding rolls 20 and 30. These side plates 71 and 72 are coupled to each other via the tie rods 79 a to 79 d extending in the horizontal direction. The tie rods 79 a and 79 d are omitted from the illustration of FIG. 1(b) for the sake of improvement of visibility of the pressure-bonding rolls 20 and 30

As illustrated in FIG. 1(a), the side plate 72 includes grooves 83 and 84 formed along the vertical direction. In the present embodiment, the grooves 83 and 84 are formed in parallel with each other along the vertical direction. Further, the grooves 83 and 84 are each formed from a top end of the side plate 72 to a position that does not reach a bottom end, and penetrate through the side plate 72 in the horizontal direction. The bearing 22, which bears the first pressure-bonding roll 20, and the bearing 32, which bears the second pressure-bonding roll 30 are inserted in the groove 83. A bearing 26, which bears the first tension roll 23, and a bearing 36, which bears the second tension roll 33, are inserted in the groove 84. In the groove 84, a spacer 86 is inserted between the bearing 26 and the bearing 36.

The side plate 71 is shaped identically to the side plate 72, and thus the side plate 71 includes grooves 81 and 82 corresponding to the grooves 83 and 84, respectively (the grooves 81 and 82 are not illustrated in FIG. 1). The bearing 21, which bears the first pressure-bonding roll 20, and the bearing 31, which bears the second pressure-bonding roll 30 are inserted in the groove 81. A bearing 25, which bears the first tension roll 23, and a bearing 35, which bears the second tension roll 33, are inserted in the groove 82. In the groove 82, a spacer 85 is inserted between the bearing 25 and the bearing 35 (refer to FIG. 3(a), which will be described below).

According to this holding member 70, the grooves 81 to 84 allow the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33 to be appropriately positioned, and also significantly facilitates attachment of the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33 to the lamination unit 10. Further, in the present embodiment, the grooves 81 to 84 are formed in such a positional relationship that respective tension forces of the annular flat belts 24 and 34 are kept at tension forces required when the lamination unit 10 is in operation. Therefore, the respective tensions of the annular flat belts 24 and 34 are automatically adjusted by inserting the first pressure-bonding roll 20 and the first tension roll 23 with the first annular flat belt 24 extending across therebetween, and the second pressure-bonding roll 30 and the second tension roll 33 with the second annular flat belt 34 extending across therebetween, into the grooves 81 to 84. This automatic adjustment facilitates a process of replacing at least one of the annular flat belts 24 and 34, the pressure-bonding rolls 20 and 30, and the tension rolls 23 and 33.

Further, support plates 77 and 78 are provided outside the side plates 71 and 72 of the holding member 70. The bearings 37 and 38 disposed at the ends of the second pressure-bonding roll 30 are placed on the support plates 77 and 78, respectively. The support plates 77 and 78 are configured to be displaceable upwardly and downwardly along the rod-shaped guides 73 and 74 extending in the vertical direction. These support plates 77 and 78 are biased upwardly by the springs 75 and 76 disposed between bottom ends of the guides 73 and 74 and the support plates 77 and 78, respectively. Biasing forces with which the springs 75 and 76 upwardly bias the support plates 77 and 78, respectively, are transmitted to the second pressure-bonding roll 30 via the bearings 37 and 38, and this transmission allows the first pressure-bonding roll 20 and the second pressure-bonding roll 30 to be kept in a positional relationship spaced apart from each other in the vertical direction as illustrated in FIG. 1. Further, the second pressure-bonding roll 30 is biased by the springs 75 and 76 upwardly, i.e., toward the pressure application roll 50, which allows the second annular flat belt 34 to be kept in contact with the pressure application roll 50 even when the driving mechanisms 61 and 62 do not press the pressure application roll 50 downwardly. According to this configuration, heat of the heater 55 included in the pressure application roll 50 is constantly transmitted to the second annular flat belt 34.

The above-described holding member 70 is configured detachably from the lamination unit 10 together with the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33 with the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33 remaining held by the holding member 70. More specifically, guides 94 and 95 are provided on a mounting plate 96 to be used to mount the holding member 70. The guides 94 and 95 extend in a direction perpendicular to the direction in which the pressure-bonding rolls 20 and 30 extend in the horizontal direction. The holding member 70 is configured detachably from the lamination unit 10 by being slid along these guides 94 and 95, and is positionally fixed at a predetermined position by a fixation member (not illustrated).

In the above-described lamination unit 10, as illustrated in FIG. 1(a), a substrate S is conveyed to between the first pressure-bonding roll 20 and the second pressure-bonding 30 by the substrate conveyance apparatus (not illustrated), and films F are also conveyed to both surfaces of the substrate S by the film conveyance apparatus (not illustrated), respectively. FIG. 1(a) illustrates that the substrate S is being conveyed to between the pressure-bonding rolls 20 and 30 with the films F respectively tentatively bonded to ends of the substrate S in an advancing direction.

Then, as illustrated in FIG. 2, the lamination unit 10 drives the driving mechanisms 61 and 62 to displace the pressure application roll 50 downwardly. This displacement causes the second pressure-bonding roll 30 to be displaced downwardly along the grooves 81 and 83 by being pressed by the pressure application roll 50. As a result, a pressing force is applied to the substrate S and the films F set between the first pressure-bonding roll 20 and the second pressure-bonding 30 (more specifically, between the first annular flat belt 24 and the second annular flat belt 34), thereby pressure-bonding the films F onto the substrate S. FIG. 2(a) illustrates that the films F are being respectively supplied to the both surfaces of the substrate S along the film guides 65 and 66 respectively provided below and above the substrate S, in synchronization with the conveyance of the substrate S. As illustrated, the film guides 65 and 66 are positionally fixed. The film guides 65 and 66 and the films F are omitted from the illustration of FIG. 2(b). The substrate S with the films F pressure-bonded thereon is conveyed on assist rollers 91 and 92 provided between the side plates 71 and 72, and is further conveyed on a conveyance roller 93. The conveyance roller 93 is mounted detachably from the lamination unit 10. The lamination unit 10 is usable not only when the films F are pressure-bounded onto the both surfaces of the substrate S, but also when the film F is pressure-bonded onto only any one of the surfaces of the substrate S.

The above-described lamination unit 10 is subject to deposition of a photoresist contained in the films F on the annular flat belts 24 and 34 that contact the films F at the time of the pressure-bonding operation, thereby raising the necessity of replacing the annular flat belts 24 and 34 on a regular basis. A procedure at the time of this replacement will be described now. The replacement process is performed in the state illustrated in FIG. 1, i.e., when the pressure application roll 50 is displaced in the second direction (the direction in which the second pressure-bonding roll 30 is displaced away from the first pressure-bonding roll 30). In the replacement process, first, the conveyance roller 93 is detached from the lamination unit 10 to secure a path along which the holding member 70 can be detached as illustrated in FIG. 3. FIG. 3(b) corresponds to FIG. 1(b), except for including illustration of the tie rods 79 a and 79 d while omitting illustration of a part of the components (the driving mechanisms 61 and 62, and the like) conversely. FIG. 3(a) is a side view of the lamination unit 10 illustrated in FIG. 3(b), except for including the illustration of the part of the components (the driving mechanisms 61 and 62, and the like) omitted in FIG. 3(b).

After the conveyance roller 93 is detached, next, the holding member 70 is detached from the lamination unit 10 by being slid with the pressure-bonding rolls 20 and 30, the tension rolls 23 and 33, and the annular flat belts 24 and 34 remaining mounted thereon as illustrated in FIG. 4. FIG. 4(a) corresponds to FIG. 3(a). FIG. 4(b) illustrates the lamination unit 10 illustrated in FIG. 4(a) taken along a line indicated by arrows C and C, while also illustrating the support roll 40 and the pressure application roll 50 by respective two-dot chain lines.

After the holding member 70 is detached, next, the pressure-bonding roller 20 and 30, the tension rolls 23 and 33, and the annular flat belts 24 and 34 are dismounted from the holding member 70 as illustrated in FIG. 5. After that, the annular flat belts 24 and 34 can be easily detached from the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33, and replaced. Needless to say, the pressure-bonding rolls 20 and 30 and the tension rolls 23 and 33 can also be replaced as necessary. After the annular flat belt(s) 24 and/or 34 is/are replaced, the holding member 70 and the conveyance roller 93 are attached to the lamination unit 10 by a reverse procedure of the procedure illustrated in FIGS. 3 to 5.

According to the laminator including the above-described lamination unit 10, the support roll 40 and the pressure application roll 50 do not contact the films F and therefore normally do not have to be replaced. Therefore, the support roll 40 and the pressure application roll 50 can be increased in diameter and thus enhanced in rigidity without requiring increases in respective diameters of the pressure-bonding rolls 20 and 30, which can prevent or reduce deformation of the pressure-bonding rolls 20 and 30 and achieve evenness of the pressing force applied to the substrate. In other words, the present laminator can realize both the improvement of process efficiency regarding the replacement of the component and the evenness of the pressing force at the same time. Further, the pressure application roll 50 pressure-bonds the films F onto the substrate S by pressing the second pressure-bonding roll 30 along a line, so that an even pressure distribution can be acquired compared to the conventional method that presses the ends of the second pressure-bonding roll 30. Further, the pressure-bonding bolls 20 and 30 do not have to be increased in diameter to achieve the evenness of the pressing force, i.e., the pressure-bonding rolls 20 and 30 can be kept small in diameter, which leads to an increase in a linear pressure in the direction in which the pressure-bonding rolls 20 and 30 extend when the films are pressure-bonded. As a result, the films F can be pressure-bonded onto the substrate S with a further low pressing force. Further, the laminator including the lamination unit 10 allows the pressure-bonding rolls 20 and 30 to be reduced in diameter, i.e., lightened in weight, thereby facilitating the process of detaching and attaching the pressure-bonding rolls 20 and 30. Furthermore, this configuration also leads to reductions in heat capacities of the pressure-bonding rolls 20 and 30, thereby allowing respective temperatures of the pressure-bonding rolls 20 and 30 to drop quickly after the operation of the laminator is stopped. Therefore, the process of detaching and attaching the pressure-bonding rolls 20 and 30 can be started soon after the operation of the laminator is stopped.

Further, the lamination unit 10 includes the heaters 45 and 55 inside the support roll 40 and the pressure application roll 50, respectively, thereby allowing the pressure-bonding rolls 20 and 30 to be further reduced in diameter compared to the pressure-bonding rolls 20 and 30 including respective heating units therein. Therefore, the present laminator can further enhance the above-described advantageous effects brought about from the reductions in the respective diameters of the pressure-bonding rolls 20 and 30.

Further, according to the lamination unit 10, the second annular flat belt 34 is kept in contact with the pressure application roll 50 even when the driving mechanisms 61 and 62 do not press the pressure application roll 50 downwardly. Therefore, the second annular flat belt 34 can be efficiently indirectly heated with the aid of the heater 55 included in the pressure application roll 50. In addition, even when the pressure application roll 50 is displaced in the second direction (in the direction in which the second pressure-bonding roll 30 is displaced away from the first pressure-bonding roll 20) after the films F are pressure-bonded onto a first substrate S, a temperature of the second annular flat belt 34 does not drop. This means that, when pressure-bonding the films F onto a second substrate S supposed to be processed after the first substrate S, the present laminator does not require a time to increase the temperature of the second annular flat bet 34 again. Therefore, the present laminator can efficiently perform the process of pressure-bonding the films, and provide high manufacturing efficiency. In other words, the laminator can realize productivity equivalent to a direct heating method even though employing an indirect heating method as described above.

Further, according to the lamination unit 10, the holding member 70 with the pressure-bonding rolls 20 and 30, the tension rolls 23 and 33, and the annular flat belts 24 and 34 remaining held thereon can be detached from the lamination unit 10 as a single unit, which facilitates the replacement process when at least one of the pressure-bonding rolls 20 and 30, the tension rolls 23 and 33, and the annular flat belts 24 and 34 falls in need of replacement. Furthermore, the photoresist contained in the films F is deposited only on the annular flat belts 24 and 34 and not deposited on the pressure-bonding rolls 20 and 30, whereby the deposition of the photoresist only raises the necessity of replacing the annular flat belt(s) 24 and/or 34. The process of replacing the annular flat belt(s) 24 and/or 34 is easy and does not require a long time. Therefore, when the annular flat belt(s) 24 and/or 34 fall(s) in need of replacement, the annular flat belt(s) 24 and/or 34 can be replaced quickly and the lamination processing can be resumed quickly. In other words, the lamination processing can be prevented from being interrupted for a long time by preparing only spares of the annular flat belts 24 and 34 in advance. On the other hand, the conventional method, which involves the contact of the pressure-bonding rolls to the film, requires preparation of spares of the pressure-bonding rolls in advance and replacement of the components including the pressure-bonding rolls to prevent the lamination processing from being interrupted for a long time. In this manner, according to the configuration of the present embodiment, the lamination processing can be efficiently performed only by preparing the annular flat belts 24 and 34 as spare items in advance without requiring the preparation of the pressure-bonding rolls in advance. The annular flat belts 24 and 34 are available at an extremely low price compared to the pressure-bonding rolls, whereby the present laminator can considerably save a cost regarding the spare items that should be prepared.

B. Second Embodiment

FIG. 6 schematically illustrates a configuration of a laminator 110 according to a second embodiment. FIG. 6 corresponds to FIG. 1, and in FIG. 6, similar components to the lamination unit 10 as the first embodiment are labeled the same reference numerals as FIG. 1. Further, the film guides 65 and 66 and the films F are omitted from the illustration of FIG. 6. In the following description, the laminator 110 will be described only referring to differences from the first embodiment. The laminator 110 is different from the first embodiment in terms of lacks of the tension rolls 23 and 24 and the annular flat belts 24 and 34. More specifically, the laminator 110 is configured in such a manner that the first pressure-bonding 20 and the support roll 40 contact each other, and the second pressure-bonding roll 30 and the pressure application roll 50 contact each other. Then, the laminator 110 pressure-bonds the films F onto the substrate S by sandwiching the substrate S and the films F directly between the first pressure-bonding roll 20 and the second pressure-bonding roll 30 (i.e., without intervention of another component). Therefore, the springs 75 and 76 keeps the second pressure-bonding roll 30 and the pressure application roll 50 in contact with each other by biasing the second pressure-bonding roll 30 toward one side where the pressure application roll 50 is located. Further, a holding member 170 of the laminator 110 does not include the grooves 83 and 84 because of the above-described differences. Further, the laminator 110 does not include the spacers 85 and 86 and the assist roller 92. Other than that, the laminator 110 is the same as the first embodiment.

According to this laminator 110, the laminator can preferably achieve the above-described advantageous effects in the first embodiment except for the advantageous effects brought about from the annular flat belts 24 and 34. Moreover, the first pressure-bonding roll 20 and the support roll 40 contact each other, and the second pressure-bonding roll 30 and the pressure application roll 50 contact each other, which can improve efficiency of respective heat transfers from the heaters 45 and 55 to the pressure-bonding rolls 20 and 30.

Having described how the present invention can be embodied based on several exemplary embodiments, the above-described exemplary embodiments of the present invention are intended only to facilitate the understanding of the present invention, and not to limit the present invention thereto. Needless to say, the present invention can be modified or improved without departing from the spirit of the present invention, and includes equivalents thereof. Further, the individual components described in the claims and the specification can be arbitrarily combined or omitted within a range that allows them to remain capable of achieving at least a part of the above-described objects or producing at least a part of the above-described advantageous effects. For example, the heater 45 may be provided inside the first pressure-bonding roll 20 instead of being provided inside the support roll 40. The heater 55 may be provided inside the second pressure-bonding roll 30 instead of being provided inside the pressure application roll 50. Even this configuration preferably achieves the advantageous effect of being able to acquire the even pressure distribution.

REFERENCE SIGNS LIST

-   -   10, 110 lamination unit     -   20 first pressure-bonding roll     -   21, 22 bearing     -   23 first tension roll     -   24 first annular flat belt     -   25, 26 bearing     -   30 second pressure-bonding roll     -   31, 32, 35, 36, 37, 38 bearing     -   33 second tension roll     -   34 second annular flat belt     -   40 support roll     -   41, 42 bearing     -   45 heater     -   50 pressure application roll     -   51, 52 bearing     -   53, 54 bearing casing     -   55 heater     -   61, 62 driving mechanism     -   63, 64 guide     -   65, 66 film guide     -   70, 170 holding member     -   71, 72 side plate     -   73, 74 guide     -   75, 76 spring     -   77, 78 support plate     -   79 a to 79 d tie rod     -   81, 82, 83, 84 groove     -   85, 86 spacer     -   91, 92 assist roller     -   93 conveyance roller     -   94, 95 guide     -   96 mounting plate     -   S substrate     -   F film 

What is claimed is:
 1. A laminator for pressure-bonding a film onto a substrate, the laminator comprising: a pair of pressure-bonding rolls including a positionally fixed first pressure-bonding roll, and a second pressure-bonding roll disposed above the first pressure-bonding roll and configured to be displaceable in a direction toward and a direction away from the first pressure-bonding roll, the pair of pressure-bonding rolls being configured to pressure-bond the film onto the substrate by sandwiching the substrate and the film between the first pressure-bonding roll and the second pressure-bonding roll; a support roll disposed in parallel with the first pressure-bonding roll below the first pressure-bonding roll and configured to support the first pressure-bonding roll; a pressure application roll disposed in parallel with the second pressure-bonding roll above the second pressure-bonding roll, the pressure application roll being configured to be displaceable in a first direction that is the direction in which the second pressure-bonding roll is displaced toward the first pressure-bonding roll and a second direction that is the direction in which the second pressure-bonding roll is displaced away from the first pressure-bonding roll, the pressure application roll being also configured to press the second pressure-bonding roll toward one side where the first pressure-bonding roll is located by being displaced in the first direction; and a driving mechanism configured to displace the pressure application roll in the first direction and the second direction.
 2. The laminator according to claim 1, wherein the support roll is disposed in contact with the first pressure-bonding roll, wherein the pressure application roll contacts the second pressure-bonding roll at least when the pressure application roll is displaced in the first direction, and wherein the pair of pressure-bonding rolls pressure-bonds the film onto the substrate by sandwiching the substrate and the film directly between the first pressure-bonding roll and the second pressure-bonding roll.
 3. The laminator according to claim 1, wherein the support roll includes a first heating unit inside the support roll, and wherein the pressure application roll includes a second heating unit inside the pressure application roll.
 4. The laminator according to claim 3, further comprising a biasing member configured to keep the second pressure-bonding roll and the pressure application roll in contact with each other by biasing the second pressure-bonding roll toward one side where the pressure application roll is located.
 5. The laminator according to claim 2, further comprising a holding member configured to hold the first pressure-bonding roll and the second pressure-bonding roll, the holding member being configured detachably from the laminator together with the first pressure-bonding roll and the second pressure-bonding roll with the first pressure-bonding roll and the second pressure-bonding roll remaining held by the holding member.
 6. The laminator according to claim 1, further comprising: a first tension roll and a second tension roll; a first annular flat belt extending between the first pressure-bonding roll and the first tension roll; and a second annular flat belt extending between the second pressure-bonding roll and the second tension roll.
 7. The laminator according to claim 6, wherein the support roll includes a first heating unit inside the support roll, and wherein the pressure application roll includes a second heating unit inside the pressure application roll.
 8. The laminator according to claim 7, further comprising a biasing member configured to keep the second annular flat belt and the pressure application roll in contact with each other by biasing the second pressure-bonding roll toward one side where the pressure application roll is located.
 9. The laminator according to claim 6, further comprising a holding member configured to hold the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll in such a positional relationship that respective tension forces of the first annular flat belt and the second annular flat belt are kept at tension forces required when the laminator is in operation.
 10. The laminator according to claim 9, wherein the holding member is configured detachably from the laminator together with the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll with the first pressure-bonding roll, the second pressure-bonding roll, the first tension roll, and the second tension roll remaining held by the holding member.
 11. The laminator according to claim 1, wherein an outer diameter of the first pressure-bonding roll is smaller than an outer diameter of the support roll, and wherein an outer diameter of the second pressure-bonding roll is smaller than an outer diameter of the pressure application roll. 